Lipoprotein subfractions, erythrocyte membrane cholesterol in coronary artery disease: A cross-sectional clinical study

BackgroundAtherosclerosis is a lipid-driven inflammatory disease in which plasma lipoproteins and cellular cholesterol pools contribute to coronary artery disease (CAD). Lipoprotein subfractions and erythrocyte membrane cholesterol (EMC) have each been linked to CAD, but their combined behavior across angiographic stages remains insufficiently characterized. EMC may also be relevant to blood flow properties and microcirculatory function.MethodsWe studied 122 patients undergoing coronary angiography and 64 controls. CAD severity was classified by the number of diseased vessels. Plasma lipid profile, LDL and HDL subfractions, atherogenic indices, EMC, and C-reactive protein were analyzed using multivariable regression, ANCOVA, ROC analysis, and an exploratory multi-marker approach.ResultsConventional lipid parameters showed limited group differences, whereas sdLDL, HDL subfractions, EMC, CRP, and selected lipid ratios differed across CAD severity groups. EMC increased across CAD categories and remained associated with CAD after adjustment for conventional lipid variables. Among lipid-related variables, EMC showed the most consistent association with angiographically defined CAD.ConclusionsEMC may provide complementary hemorheology- and microcirculation-relevant information in angiographically defined CAD. Lipoprotein subfractions and composite lipid indices may offer adjunctive characterization of CAD-related lipid remodeling.